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Improving Pedestrian Safety atUnsignalized Crossings
Shawn Turner, P.E.Texas A&M Transportation Institute
Overview of Presentation
• What are the issues/problems?• Framework for crossing treatments
– Marked crosswalk– Enhanced crosswalk– Active treatment– “Red” treatment– Full traffic signal
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Unsignalized Pedestrian Crossing
• No motor vehicle traffic signal control on main street
• Pedestrian crossing may be at intersecting street or mid‐block
• Typically a marked crosswalk, but not necessarily
• More common with larger block size (suburbs)
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Example 2
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Problems at Unsignalized Crossings
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Problems at Unsignalized Crossings
• Confusion about right‐of‐way–Who yields / stops ?–Pedestrian must be in crosswalk
• Difficulty judging acceptable gaps• Excessive delay to pedestrians
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Problems × 3
• High‐speed arterial streets• 2 or more lanes in both directions• Mid‐block transit stops• Limited access control
– Commercial driveways– Center two‐way left turn lane
• Low pedestrian volumes (does not satisfy traffic signal warrant)
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NCHRP Report 562 / TCRP Report 112
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• Recommend treatments for high‐speed, high‐volume roadways
• Recommend modifications to MUTCD pedestrian traffic signal warrant
FHWA Study on Marked vs. Unmarked Crosswalks
• Depends on:– Traffic volume– Traffic speed– Road width/median
1. Marked Crosswalk2. Consider Enhancement
to Marking3. Must Add Enhancement
to Marking11
Safety Benefits of Other Treatments
• Difficult to quantify for each treatment• Insufficient crash data for experimental treatments
• Lead to use of safety surrogates– % motorists yielding to pedestrians– Motorist behavior (speed reduction)– Pedestrian behavior
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What are “treatments”?
• Geometric design• Traffic calming• Static warning signs• Continuous flashing beacons• Activated beacons
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Median Crossing Island
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Median Crossing Island
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Curb Extension (Mid‐Block, Transit Stop)
17Curb Extension (Intersection)
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Raised Crosswalks
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Roadway / Lane Narrowing
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Crossing Sign + Markings
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In‐Street Crossing Signs
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High‐Visibility Signs / Markings
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High‐Visibility Signs / Markings
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Advance Yield / Stop Line
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In‐Roadway Warning Lights
26Overhead Flashing Amber Beacons
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Overhead Flashing Amber Beacons
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Half Signal
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Pedestrian Hybrid Beacon (“HAWK”)
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Pedestrian Hybrid Beacon (“HAWK”)
Research Question
• What treatment is most (cost)‐effective in different street contexts?
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Research Approach
• Evaluate motorist yielding for different treatments in different street contexts
• Higher yielding = less delay, more safe• Lower yielding = more delay, less safe• Using Highway Capacity Manual pedestrian delay thresholds, develop algorithm to determine treatment type
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Presto!! Shazam!!
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34Traffic Volume
Pede
stria
n Vo
lum
e/D
eman
d
No crosswalkmarking
Basic or enhancedmarking/signing
“Yellow”treatment
“Red”treatment
Traffic signalper MUTCD
IncreasingVisibility and/orTraffic Control
Increasing traffic volume
Increasingpedestrianvolume/demand
2 Lanes, <55 km/h
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MarkedCrosswalk
Red
Enhanced/Active (E/A)
E/A High,Red Low
Traffic Signal(Proposed MUTCD Warrant)
6 Lanes, >55 km/h
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RedEnhanced/Active (E/A)
E/A High,Red Low
Traffic Signal(Proposed MUTCD Warrant)
NO Marked Crosswalk Only
Resources / Additional Reading
• NCHRP Report 562 / TCRP Report 112: http://onlinepubs.trb.org/onlinepubs/nchrp/nchrp_rpt_562.pdf
• Alternative Treatments for At‐Grade Pedestrian Crossings, ITE 2001 ($37.50 US)• City of Boulder (CO) Pedestrian Crossing Treatment Installation Guidelines,
http://www.bouldercolorado.gov/index.php?option=com_content&view=article&id=17386&Itemid=5587
• Safety Effects of Marked Versus Unmarked Crosswalks at Uncontrolled Locations, FHWA 2005, http://www.fhwa.dot.gov/publications/research/safety/04100/04100.pdf
• Pedestrian Crossing Control Guide, TAC 2012 ($155 CN)
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